What is a double-storey extension?
A double-storey extension (also called a two-storey extension) adds rooms on both the ground and first floor in one build. It typically gives a larger kitchen or living space downstairs and an extra bedroom or bathroom above.
How much does a double-storey extension cost in Market Harborough?
In Market Harborough, a double-storey extension typically costs £1,550–£2,400 per m² of floor area (both floors), including VAT at 20% (standard rate). For a typical 36 m² project that is roughly £56,000–£86,500. Prices across the East Midlands are typically 5% below the UK average for this kind of work, which is reflected in the range for Market Harborough. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (25 m²) | £39,000–£60,000 |
| Typical project (36 m²) | £56,000–£86,500 |
| Larger project (50 m²) | £77,500–£120,000 |
| Rate per m² | £1,550–£2,400 |
Your quote will depend mainly on:
- Brick matching and external finishes
- Scaffolding and access to the rear
- Steel beams where walls are opened up
- Total floor area across both floors
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a double-storey extension in Market Harborough?
Whether you need planning permission depends on your house and its location in England. In England an extension of more than one storey can only be permitted development at the rear, no more than 3 metres deep and at least 7 metres from the rear boundary, with matching materials and any upper side windows obscure-glazed. Most double-storey extensions therefore go through a householder planning application.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
The work we manage on a double-storey extension:
- Structural engineer’s calculations
- Electrics, heating, plumbing and plastering
- Building control sign-off
- Brick or block walls, floors and a roof tied into the house
- Design drawings and planning application
- Windows, doors and staircase alterations
How long does it take?
Build time is typically 14 to 20 weeks on site, after planning and building control approval. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in Market Harborough
In the East Midlands, many estates built since the 1960s have integral garages that convert well into a study or bedroom.
We work across Market Harborough and neighbouring areas such as Corby, Kettering and Wigston Magna. Postcodes we cover in Market Harborough include LE16.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about double-storey extensions in Market Harborough
Is a double-storey extension cheaper per square metre?
Usually yes. You pay for one set of foundations and one roof but get two floors of space, so the cost per square metre is often lower than a single-storey extension.
How much does a double-storey extension cost in Market Harborough?
In Market Harborough, a double-storey extension typically costs £1,550–£2,400 per m² of floor area (both floors), including VAT at 20% (standard rate). A typical 36 m² project comes to roughly £56,000–£86,500. Your fixed price depends on the survey and drawings.
Can I live at home during the work?
Most families stay put. The shell is built first and the house is opened up late in the job, so disruption inside is limited to a few weeks.
Who approves a double-storey extension in Market Harborough?
Planning matters in Market Harborough go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
What drawings do I need?
Planning drawings for the application, then more detailed building regulations drawings and structural calculations for building control. We prepare both.